Process for finishing textile material and product



United States Patent PROCESS FOR FINISHING TEXTILE. MATERIAL AND PRODUCT Elmer H. Rossin, Melrose, Mass, assignor to Monsanto Chemical Company, St. Louis, M0.

N Drawing. Application January 27, 1954, Serial No. 406,599

14 Claims. (Cl. 11711) The present invention relates to the finishing of textile materials containing nylon fibers or filaments, and it more particularly relates to the treatment of such textile materials to improve their properties and provide a finish which is flame resistant. The present invention also relates to compositions suitable for treating such textile materials, and to textile materials containing nylon fibers or filaments having an improved finish.

It has been proposed, heretofore, to treat nylon fabrics which are normally limp, lack body and melt but do not propagate flame with melamine-formaldehyde or ureaformaldehyde condensation products and then cure the condensation products in situ to the water-insoluble state. This treatment does improve the body of the fabric and also stiitens the fabric, but has the disadvantage of making the fabric quite flammable. It has also been pro posed to increase the body and stiifness of nylon fabrics which are normally limp and lack body by the application of starch solutions followed by drying. While this procedure does give the result sought, the finish is not durable to laundering and thus is not suitable in those instances where the fabric must be subjected to a number of launderings or aqueous cleaning operations.

In accordance with the present invention, on the other hand, it is not only possible to increase the body and stiffness of textiles containing nylon or linear synthetic polyamides, but it is also possible to provide a finish which is also durable to aqueous and organic solvent cleaning operations and is flame-resistant.

It is, accordingly, one object of this invention to provide a process of producing a durable, stiff, flame-resistant finish on textile material's comprising nylon or fiberforming linear polyamides.

It is a further object of this invention to provide a novel finishing composition which is particularly suitable for application to textile materials containing nylon or fiber-forming linear polyamides to provide a durable, stitf, flame-resistant finish on such materials.

It is a further object of this invention to provide a nylon or fiber-forming linear polyamide textile material having a stiif and durable finish which is flame-resistant and resistant to laundering and dry cleaning.

Still further objects and advantages of this invention will become apparent from the following description and the appended claims.

The present invention provides a finishing composition comprising (1) a water-soluble, fully methylolated het erocyclic compound having a saturated ring consisting only of carbon atoms and at least two nitrogen atoms each of which are attached to the same carbon atom in the ring and have the remaining valence satisfied by a methylol (CH2OH) group, there being at least one oxygen or sulfur atom attached to the carbon atom in the ring to which the two nitrogen atoms are attached, for example, a compound such as dimethylol ethylene urea, and (2) thiourea. The composition may be dry or substantially dry or may be in the form of an aqueous solution of the named ingredients. The compositionmay comprise, in addition to the ingredients named above, a latent curing catalyst such as ammonium chloride, stiffening agents such as partially polymerized urea-formaldehyde condensation products or alkyl ethers, preferably methyl ethers, of such condensation products, and/or small amounts of softening agents to impart slipperiness to the finish produced from the compositions. The latent curing catalyst is preferably omitted from the composition until just prior to use since such catalyst generally has an adverse effect on the storage or shelf life of the composition. However, when the compositions are employed in the textile treating processes hereinafter described, it is essential to add a catalyst, and preferably a latent curing catalyst, to the composition in order to obtain a durable finish on the textile.

A wide variety of latent curing catalysts may be employed such as the ammonium or amine salts of mineraland organic acids. As examples of ammonium salts which may be used may be mentioned ammonium chloride, diammonium hydrogen phosphate, ammonium formate, ammonium acetate and the like. As examples of amine salts which maybe employed may be mentioned amine salts derived from a primary alkyl amine and an acid as, for example, ethyl amine hydrochloride or phosphate, propyl amine hydrochloride or phosphate, butyl amine hydrochloride or phosphate, sec-butyl amine hydrochloride or phosphate and the like; amine salts derived from a secondary alkyl amine and an acid as, for example, diethyl amine hydrochloride or phosphate, dipropyl amine hydrochloride or phosphate, dibutyl amine hydrochloride or phosphate and the like; amine salts derived from an acid and a primary aliphatic amine hav ing from 1 to 4 hydroxyl groups as, for example, monoethanolamine hydrochloride or phosphate, isopropanol amine hydrochloride or phosphate, l-amino-Z-methyl propanol-Z hydrochloride or phosphate, Z-methyl-Z-amino propanol-1 hydrochloride or phosphate, Z-amino butanediol-1,4 hydrochloride or phosphate and the like; and amine salts derived from an acid and a secondary aliphatic amine having from 1 to 4 hydroxyl groups as, for example, dietha-nolamine hydrochloride or phosphate, methyl amino ethanol hydrochloride or phosphate, ethyl amino ethanol. hydrochloride or phosphate, N-dipropanediol-l,3 amine hydrochloride or phosphate, and the like. The latent curing catalysts are generally employed in amounts of 1 to 10% by weight, based on the fully methylolated heterocyclic compound such as dimethylol ethylene urea, but the preferred amounts are 3 to 7% by weight based on the fully methylolated heterocyclic compound.

As mentioned above other stiffening agents may be used in. the composition, but the preferred stiffening agents are cooked or partially polymerized urea-formaldehyde condensation products or partially polymerized methyl ether of urea-formaldehyde condensation products and particularly those partially polymerized condensation products which are water-soluble to water-dispersible. As examples of other stiffening agents which may be used in the compositions may be mentioned starch, casein, casein, formaldehyde reaction products, ammonium or amine salts of styrene-maleic anhydride copolymers or ammonium or amine salts of copolymers of to 98 mol percent of vinyl acetate and 20 to 2 mol percent of crotonic acid and the like. Such stiifening agents are usually employed in amounts up to 50% by weight, based on the fully methylolated heterocyclic compound such as dimethylol ethylene urea, depending on the amount of stiffening desired.

A large variety of softening agents may be used in the compositions of this invention to provide a finish having. a slippery feel without materially detracting from the stiffness of the finish. As examples of suitable softening agents which may be used may be mentioned cationic surface active agents such as cetyl dimethyl benzyl ammonium chloride or bromide, cetyl pyridinium chloride or bromide and the like, and anionic surface active I agents such as decyl or dodecyl benzene sodium sulfonate, sodium dioctyl sulfo succinate and sodium fatty alcohol sulfonates or sulfates and the like. The softening agent is usually employed in small amounts, for example, from 1 to 10% on the weight of the fully methylolated heterocyclic compound, but amounts up to 40% on the weight of the fully methylolated heterocyclic compound may be used in those instances when the composltlon is applied to nylon textile materials which are subsequently subjected to a mechanical finishing operation such as glazing or embossing. i

The compositions may comprise various concentrations of thiourea and the fully methylolated heterocyclic compound such as dimethylol ethylene urea, the concentration of these ingredients being dependent on the purpose for which the composition is used, and to some extent on whether the composition is in a dry state or in the form of a solution. However, for the treatment of textiles containing nylon or a fiber-forming linear polyamide, it is desirable to use aqueous compositions, and such compositions may contain from to 65 by weight of thiourea and the fully methylolated heterocyclic compound. When the compositions are employed for finishing textiles containing nylon or a fiber-forming linear polyamide, the ratio of thiourea to the fully methylolated heterocyclic compound in the composition is important. If too little thiourea is employed the finish obtained is usually not sufficiently flame-resistant, whereas if the amount of thiourea employed is too high the finish obtained tends to yellow and also is notas durable to laundering as is desired. Usually it is necessary to employ at least 3% of thiourea but not in excess of 40% of thiourea, based on the weight of the fully methylolated heterocyclic compound such as dimethylol ethylene urea in the composition. Usually, best results are obtained by using from 5 to 35% of thiourea based on the weight of the fully methylolated heterocyclic compound, and such amounts are preferred.

The fully methylolated heterocyclic compounds employed in the compositions of this invention have a saturated ring consisting only of carbon atoms and at least two nitrogen atoms, preferably a saturated ring consisting of 3 carbon atoms and 2 nitrogen atoms, each of the two nitrogen atoms being attached to the same carbon atom in the ring and having the remaining valence satisfied by a methylol (CH2OH) group, there being at least one oxygen or sulfur atom attached to the ring on a carbon atom which is adjacent to the two nitrogen atoms, the remaining valences of the carbon atoms in the ring being satisfied by hydrogen atoms. Preferred compounds of this type are those having from 3 to 4 carbon atoms having oxygen or sulfur atoms attached to each carbon atom in-the ring which is adjacent to two nitrogen atoms and having 2 or 4 nitrogen atoms in the ring each pair of which is one carbon atom removed from the other nitrogen atom in the pair, the remaining valence of the nitrogen atoms being satisfied by a methylol (CH2OH) group attached to such nitrogen atom, the remaining valences of the carbon atoms in the ring being satisfied by hydrogen atoms. As examples of fully methylolated heterocyclic compounds which may be used may be mentioned dimethylol ethylene urea (also known as dimethylol imidazolidone- 2), dimethylol ethylene thiourea, dimethylol l-Z propylene urea, dimethylol l-2 propylene thiourea, dimethylol l-3 propylene urea, dimethylol 1-3 propylene thiourea, dimethylol 1-3 butylene urea, dimethylol 2-3 butylene urea, tetramethylol acetylene diureine, dimethylol hydantoin and the like. However, from the standpoint of availability, cost and the results obtained, it is preferred to employ dimethylol ethylene urea as this compound does give a result which is superior, for the purposes of this invention, to that obtained by the use of the other fully methylolated heterocyclic compounds of the type described.

The compounds disclosed in the preceding paragraph are sometimes described by the following nomenclature; dimethylol ethylene urea is 1,3-bis(hydroxymethyl)-2- oxo imidazolidine or 1,3 bis(hydroxymethyl) imidazolidone-2, dimethylol 1,2-propylene urea is 1,3-bis(hydroxymethyl)-2-oxo-4 methyl imidazolidine or 1,3-bis- (hydroxymethyl)-4-methyl-imidazolidone 2, dimethylol 2,3-butylene urea is l,3-bis(hydroxymethyl)-2-oxo-4,5- dimethyl-imidazolidine or 1,3-bis(hydroxymethyl)-4,5-dimethyl-imidazolidone-Z, dimethylol 1,3-propylene urea is l,3-bis(hydroxymethyl)-2-oxo-hexahydro pyrimidine or r 1,3 bis(hydroxymethyDhexahydro pyrimidone 2, di-

methylol 1,3-butylene urea is 1,3-bis(hydroxymethyl)-2- oxo-4-methyl-hexahydro pyrimidine or l,3-bis(hydroxymethy1)-4-methy1- hexahydro pyrimidone-Z, dimethylol hydantoin is l,3-bis(hydroxymethyl)-2,4-dioxo imidazolidine or 1,3 bis(hydroxymethyl)imidazolidione-2,4, and tetramethylol acetylene diurein is l,3,4,6-tetrakis(hydroxymethyl)2, 5 dioxo-hexahydro[imidazo1o-7',8':7,8- imidazollidine or 1,3,4,6-tetrakis(hydroxymethyl)-hexahydro[imidazolo-7',8':7,8-imidazollidione-2,5.

The operative compounds may be represented by the following formula:

wherein Z is a divalent bridging radical selected from the group consisting of:

R being selected from the group consisting of hydrogen and CH3 and X being a chalcogen selected from the group consisting of oxygen and sulfur.

The textile treating processes of this invention are carried out, in general, by applying the compositions hereinbefore described as suitable for treatment of nylon in the form of an aqueous solution to a textile material containing at least 50% by weight of nylon or a fiberforming linear polyamide, and subsequently heating the textile material at an elevated temperature, but below the temperature at which the textile material is damaged by heat, until a water-insoluble finish is obtained or until a finish is obtained which is durable to laundering. The treating solution used is preferably neutral to slightly alkaline and preferably has a pH between about 7.0 and 10.0, but it is possible in some instances to employ slightly acidic solutions having a pH between about 5 and 7.

The composition may be applied to the textile material in various ways. For example, the composition may be sprayed on the textile material or the textile material may be immersed or dipped in the composition and then removed. In either case excess composition may be removed from the textile material by squeezing, wringing or hydroextracting the material or by passing the material between squeeze rolls. The amount of fully methylolated heterocyclic compound and thiourea applied to the textile material is governed by the concentration of these ingredients in the composition and the amount of composition removed from the textile material by squeezing etc. These factors are ordinarily adjusted or controlled so as to apply about 5 to 65% by weight, based on the dry textile material, of' the fully methylolated heterocyclic compound and thiourea, the particular amount applied being dependent on the nature of the textile material and the amount of body and stifliness desired. For example, in the case of light nylon nettings having relatively large interstices between yarns and which are ordinarily quite limp and sleazy, it is usually desirable to apply relatively large amounts of the fully methylolated heterocyclic compound and thiourea, for instance about to 65% by weight, based on the dry nettings, in order to obtain a netting having the desired body and stiffness. On the other hand, in the case of heavier materials such as nylon upholstery fabrics which have a close weave and a fair amount of body, it is usually desirable to apply smaller amounts of the fully methylolated heterocyclic compound and thiourea, for example, about 5 to 25% by weight, based on the dry fabrics. As is pointed out previously herein in the description of the compositions, it is necessary to use at least 3 but not in excess of of thiourea, based on the weight of the fully methylolated heterocyclic compound, in order to obtain satisfactory flame-resistance and durability without detrimental yellowing, and the preferred amounts of thiourea are 5 to 35% based on the weight of the fully methylolated heterocyclic compound.

The composition applied to the textile material should have a catalyst present during the subsequent heating of the textile material in order to bring about a reaction between the fully methylolated heterocyclic compound and thiourea. Such reaction results in the formation of a water-insoluble reaction product on the textile material which is highly resistant to removal by laundering or other aqueous cleaning operations. This reaction product, which is flame-resistant, is hard and thus stiffens the textile material, but it is also sufiiciently flexible and adherent to permit flexing of the textile material without breaking the bond between the reaction product and the textile material. The catalyst, which is preferably of the latent curing type hereinbefore described, may be added to the composition before application to the textile material, this procedure being preferred, or the catalyst may be applied to the composition after the composition has been applied to the textile material.

Subsequent to the application of the composition and catalyst to the textile material, the textile material is heated at elevated temperatures. This heating may first be carried to the stage where the composition is only partially dried, that is, contains about 5 to 25% by weight of moisture, based on the dry textile material. Such procedure may be used in those instances where the textile material is mechanically finished as by glazing, embossing,

Schreinering or the like at the stage where the textile material is only partially dry. Such mechanical finishing is preferably carried out after partial drying and before the formation of the water-insoluble reaction product of the fully methylolated heterocyclic compound and thiourea. The heating of the treated textile material for purposes of complete or partial drying may be carried out at relatively low temperatures, for example, temperatures of about 125 to 250 F. The textile material is then heated at higher temperatures, but below the temperature at which the textile material is damaged. until a waterinsoluble finish is obtained or until the composition on the textile material is durable to conventional laundering. During this step the fully methylolated heterocyclic com pound and thiourea react in the presence of the catalyst to form a water-insoluble react-ion product. The temperature used during this stage of heating may vary some what, but is preferably between 275 and 400 F. The duration of heating may vary between about 10 seconds and 10 minutes, with the longer period corresponding to the lower temperature. It is generally possible, however, to obtain satisfactory results by heating for a period between 10 and seconds. The freshly treated textile material may also be dried and a water-insoluble finish produced thereon or the finish thereon rendered durable 6 to laundering in one operation by heating the freshly treated textile material at 275 to 400 F. within the time periods described above. This latter procedure is preferred.

The resulting textile material may be used directly for its intended use or it may be first given a mild water or dilute aqueous soap wash and dried.

A further understanding of the compositions, processes and textile material products of the present invention will be obtained from the following specific examples which are intended to illustrate the invention, but not to limit the scope thereof, parts and percentages being by weight.

Example I An aqueous composition was prepared by mixing an aqueous solution having a pH of,8.0 and containing 50% of dimethylol ethylene urea, 20% of thiourea, based on the weight of the dimethylol ethylene urea, and sufficient water to provide a final solution containing about 10% of dimethylol ethylene urea. The mixing was continued until a homogeneous solution was obtained. This solution, which was slightly alkaline, was stable at normal room temperature (about F.) for a period of at least 3 months.

To the solution as obtained above was added 10%, on the weight of the dimethylol ethylene urea, of a 35% aqueous solution of 2-amino-2methyl propanol-(l) hydrochloride adjusted to a pH of about 8.0 (glass electrode) with Z-amino-Z-methyl propanol-(l), as a latent curing catalyst. A piece of nylon knit fabric prepared from 40 denier nylon (polyhexamethylene-adipamide) filaments on a raschel knitting machine, which fabric had a limp and sleazy hand, was immersed in the solution and squeezed between rolls adjusted to give a 100% pick up of solution, based on the dry fabric. The treated fabric was then heated for 5 minutes at 300 F. to dry the fabric and produce a water-insoluble finish thereon. The resulting fabric not only was stiffer and had more body than the untreated fabric, but was also flame-resistant and the finish thereon was durable to dry ,cleaning or aqueous cleaning operations. When the fabric was subjected to a flame it did not burn.

A piece of all nylon knit fabric from the same roll was immersed in anaqueous solution containing 10% of a methyl ether of methylol melamine containing 3.4 mols of combined formaldehyde and 2.2 mols of combined methanol per mol of melamine and 5%, based on the methyl ether of methylol melamine, of 2-amino-2-methyl propanol-(l) hydrochloride adjusted to a pH of 8.0 with 2-amino-2-methyl propanol-(l), and the fabric was then squeezed between rolls adjusted to give a pick up of 100% pick up of solution, based on the dry fabric. The treated fabric was then heated for 5 minutes at 300 F. to dry the fabric and cure the methyl ether of methylol melamine to the water-insoluble state. The resulting fabric had more body and was stiffer than the untreated fabric and the finish thereon was durable to aqueous cleaning operations, but when the fabric was subjected to a flame it burned readily and thus was materially more flammable than the untreated nylon knit fabric.

A piece of all nylon knit fabric from the same roll was immersed in an aqueous solution containing 10% of a methyl ether of methylol melamine containing 3.4 mols of combined formaldehyde and 2.2 mols of combined methanol per mol of melamine, 20% of thiourea on the weight of the methyl ether of methylol melamine and 5%, on the weight of the methyl ether of methylol melamine, of 2-amino2-methyl propanol-(l) hydrochloride adjusted to a pH of 8.0 with 2-amino-2-methyl propanol-(l). The fabric was then squeezed between pad rolls adjusted to give a pick up of 100% of solution, based on the dry fabric, after which the fabric was heated for 5 minutes at 300 F. to dry the fabric and cure the methyl ether of methylol. melamine to the water-insoluble state. The resulting fabric had more body and was stiffer than the ungreens 7 treated fabric and the finish on the treated fabric was durable to aqueous cleaning operations, but when the fabric was subjected to a flame it burned readily and thus was considerably more flammable than the untreated nylon knit fabric.

7 Example 11 p a raschel knitting machine was immersed in the solution prepared as described in the preceding paragraph, and

the fabric was then squeezed between pad rolls adjusted to give a solution pick up of 100%, based on the dry fabric. The squeezed fabric was then heated for 5 minutes at 320 F. to dry the fabric and produce a water-insoluble finish on the surface of the filaments of the fabric. The resulting fabric had excellent body, stitfness and dimensional stability and the finish thereon was durable to dry cleaning or aqueous cleaning operations. Moreover, the fabric did not burn when subjected to an open flame.

Example III A piece of all nylon upholstery fabric prepared from 130 denier 34 filament nylon (polyhexamethylene-adipamide) filaments was immersed in an aqueous solution having a pH of about 7.5 and containing 5% of dimethylol ethylene urea, 10% of thiourea based on the weight of dimethylol ethylene urea and 5%, on the weight of the dimethylol ethylene urea, of 2-amino-2-methyl propanol- (1) hydrochloride adjusted to a pH of 8.0 with 2-amino- 2-methyl propanol-( 1). The fabric was removed from the solution and squeezed between rolls adjusted to give a pick up of 100% of the solution, based on the dry fabric weight, after which the fabric was heated for 5 minutes at 320 F. to dry the fabric and produce a water-insoluble finish thereon. The resulting fabric had good body and stifiness compared to the untreated fabric and the finish on the treated fabric was durable to dry cleaning or aqueous cleaning operations. Moreover, the fabric did not burn when subjected to an open flame.

Although the specific examples illustrate the treatment of various nylon fabrics and the products obtained therefrom, it is possible in accordance with the processes of this invention to treat nylon fibers such as nylon staple fibers or nylon filaments or nylon yarns produced from nylon staple fibers to provide such fibers or yarns with increased body and stitfness and to render them flame-resistant and durable to laundering. The present invention is most applicable, however, to the treatment of nylon fabrics to provide them with a finish which is not only durable to laundering but improves the body and stiffness of the fabrics and renders them flame-resistant. Accordingly, the treatment of fabrics is preferred.

Moreover, although the specific examples illustrate the treatment of fabrics containing 100% by weight of nylon, it is also possible in accordance with the present invention to treat textile materials such as fibers, yarns and fabrics containing at least 50% by weight of nylon, the remainder of the textile material comprising some other fibrous material such as wool, cotton, linen, regenerated cellulose such as viscose or cuprammonium rayon, cellulose acetate, vinyl chloride-vinyl acetate copolymers, polyacrylonitrile, copolymers of major amounts of acrylonitrile and minor amounts of other monomers copolymerizable therewith, polyvinylideue chloride, copolymers of vinyl chloride and vinylidene chloride, glass, asbestos, condensation products of glycols such as ethylene glycol and esters of terephthalic acid such as dimethyl terephthalate and the like. However, in such instances with the exception where the other fibrous material is glass or asbestos it is usually necessary, if an all flame-resistant textile material is desired, to treat the other fibrous material such as wool, cotton, rayon etc. with a composition which will render such fibrous material flame-resistant since the compositions of this invention usually only impart flame-resistance to the nylon portion of the textile material and do not usually impart flame-resistance to other fibrous material. This usually means that the other fibrous material must be treated with a composition capable of rendering it flame-resistant prior to the incorporation of such fibrous material with nylon in the textile material which is to be treated with the compositions of the present inventions. In view of the foregoing, it is preferred to treat textile materialswhich are composed wholly of nylon.

The term nylon as used herein is intended to include water-insoluble fiber-forming linear polyamides, particularly the water-insoluble fiber-forming linear polyamides prepared by condensing an aliphatic diamine such as hexamethylene diamine with an aliphatic polybasic acid such as adipic acid or sebacic acid, such as the fiber-forming linear polyamides described in United States Patents No. 2,071,250, No. 2,130,532 and No. 2,130,948. Of the foregoing linear polyamides it is preferred to treat textile materials containing water-insoluble .polyhexamethyleneadipamide since such materials are commercially available and are especially amenable to treatment by the processes of the present invention. The term nylon also includes fiber-forming water-insoluble linear polyamides produced from caprolactam.

What is claimed is:

1. A process of finishing a textile material containing water-insoluble nylon which comprises applying to said material an aqueous medium comprising (1) a fully methylolated heterocyclic compound having a saturated ring consisting only of carbon atoms and at least two nitrogen atoms each of which two nitrogen atoms are attached to the same carbon atom in the ring and have the remaining valence satisfied by a methylol group, there being in said compound at least one atom selected from the group consisting of oxygen and sulfur which atom is attached to the carbon atom to which the two nitrogen atoms are attached, (2) from 3 to 40% of thiourea on the weight of said compound and (3) a catalyst, and thereafter heating said material at an elevated temperature, but below the temperature at which the material is damaged, until a water-insoluble finish is formed on said material, said fully methylolated heterocyclic compound having the formula:

wherein Z is a divalent bridging radical selected from the group consisting of:

R being selected from the group consisting of hydrogen and CH3 and X being a chalcogen selected from the group consisting of oxygen and sulfur.

2. A process as in claim 1, but further characterized in that said compound is dimethylol ethylene urea.

3. A process as in claim 2, but further characterized in that the water-insoluble nylon is water-insoluble polyhexamethylene-adipamide.

4. A process of finishing a textile material containing water-insoluble nylon which comprises applying to said material an aqueous medium containing (1) dimethylol ethylene urea, (2) from to 35% by weight of thiourea, based on the dimethylol ethylene urea, and (3) from 1 to by weight of a latent curing catalyst, based on the dimethylol ethylene urea, said medium containing from 5 to 65% by weight of (1) and (2) and being supplied in an amount sufficient to provide from 5 to 65% by weight of (1) and (2), based on the dry textile material, and thereafter heating the textile material at a temperature above 275 F. but below the temperature at which the material is damaged until a water-insoluble finish is formed thereon.

5. A process as in claim 4, but further characterized in that the water-insoluble nylon i-s water-insoluble polyhexamethylene-adipamide.

6. A process as in claim 4, but further characterized in that the textile material is a fabric.

7. A process as in claim 4, but further characterized in that the textile material is a fabric composed entirely of water-insoluble nylon yarns.

8. A process as in claim 4, but further characterized in that the textile material is a fabric composed entirely of water-insoluble polyhexamethylene-adipamide yarns.

9. A process of finishing a textile fabric containing water-insoluble nylon yarns which comprises applying to said material an aqueous medium containing (1) dimethylol ethylene urea, (2) from 5 to by weight of thiourea, based on the dimethylol ethylene urea, (3) up to 50% by Weight of a stiffening agent, based on the dimethylol ethylene urea, and (4) from 1 to 10% by weight of a latent curing catalyst, based on the dimethylol ethylene urea, said medium containing from 5 to 65% by weight of (1), (2) and (3), and thereafter heating said fabric to a temperature above 275 F. but below the temperature at which the fabric is damaged, until a waterinsoluble finish is formed on said fabric.

10. A process as in claim 9, but further characterized in that said stiffening agent is a substance selected from the group consisting of a partially polymerized urea-formaldehyde condensation product and a partially polymerized methyl ether of urea-formaldehyde condensation product.

11. A process of finishing a textile fabric composed of at least 50% by weight of water-insoluble nylon and up to 50% by weight of a flame-resistant fibrous material which comprises applying to said fabric an aqueous medium containing dimethylol ethylene urea, from 3 to by weight of thiourea, based on the dimethylol ethylene urea, and a latent curing catalyst and thereafter heating said fabric to a temperature above 275 F., but below the temperature at which the fabric is damaged, until a Water-insoluble finish is formed on said fabric.

12. A process of finishing a textile fabric containing water-insoluble nylon yarns which comprises applying to said fabric an aqueous medium comprising (1) dimethylol ethylene urea, (2) from about 5 to 35% by weight of thiourea, based on the dimethylol ethylene urea, (3) from 1 to 10% by weight of a latent curing catalyst, based on the dimethylol ethylene urea, and (4) up to 40% by weight, based on the dimethylol ethylene urea, of a soft ening agent, partially drying the fabric to a moisture content of 5 to 25%, mechanically finishing the fabric, and thereafter heating the fabric at a temperature above 275 F., but below the temperature at which the fabric is damaged, until a water-insoluble finish is formed on the fabric.

13. A textile material containing water-insoluble nylon having a water-insoluble finish thereon comprising the water-insoluble reaction product of thiourea and a fully methylolated heterocyclic compound having a saturated ring consisting only of carbon atoms and at least two nitrogen atoms each of which two nitrogen atoms are attached to the same carbon atom in the ring and have the remaining valence satisfied by a methylol group, there being in said compound at least one atom selected from the group consisting of oxygen and sulfur which atom is attached to the carbon atom to which the two nitrogen atoms are attached, said fully methylolated heterocyclic compound having the formula:

wherein Z is a divalent bridging radical selected from the group consisting of:

rv-oH-bm-R' rv-oH-om-bH-m' R'-oH :=o (bu-( 11 R being selected from the group consisting of hydrogen and CH3 and X being a chalcogen selected from the group consisting of oxygen and sulfur.

14. A fabric composed entirely of water-insoluble polyhexamethylene-adipamide yarns having thereon from 5 to by weight, based on the dry fabric, of a waterinsoluble finish comprising the water-insoluble reaction product of dimethylol ethylene urea with from 5 to 35% by weight of thiourea, based on the dimethylol ethylene urea.

References Cited in the file of this patent UNITED STATES PATENTS 2,219,375 Widmer et al. Oct. 29, 1940 2,373,136 Hoover et al. Apr. 10, 1945 2,374,647 Burke et al. May 1, 1945 2,440,202 Klaber et a1 Apr. 20, 1948 2,571,238 Harris et al. Oct. 16, 1951 2,613,210 Hurwitz, Oct. 7, 1952 2,613,211 Hurwitz Oct. 7, 1952 2,624,686 Hamlet Ian. 6, 1953 2,654,763 Adkins Oct. 6, 1953 2,661,312 Richardson Dec. 1, 1953 2,729,577 Bacon et a1. Ian. 3, 1956 

12. A PROCESS OF FINISHING A TEXTILE FABRIC CONTAINING WATER-INSOLUBLE NYLON YARNS WHICH COMPRISES APPLYING TO SAID FABRIC AN AQUEOUS MEDIUM COMPRISING (1) DIMETHYLOL ETHYLENE UREA, (2) FROM ABOUT 5 TO 35% BY WEIGHT OF THIOUREA, BASED ON THE DIMETHYLOL ETYLENE UREA, (3) FROM 1 TO 10% BY WEIGHT OF A LATENT CURING CATALYST, BASED ON THE DIMETYLOL ETHYLENE UREA, AND (4) UP TO 40% BY WEIGHT, BASED ON THE DIMETHYLOL EHTYLENE UREA, OF A SOFTENING AGENT, PARTIALLY DRYING THE FABRIC TO A MOISTURE CONTENT OF 5 TO 25%, MECHANICALLY FINISHING THE FABRIC, AND THEREAFTER HEATING THE FABRIC AT A TEMPERATURE ABOVE 275* F., BUT BELOW THE TEMPERATURE AT WHICH THE FABRIC IS DAMAGED, UNTIL A WATER-INSOLUBLE FINISH IS FORMED ON THE FABRIC. 